# -*- coding: utf-8 -*-
#
# Configuration file for the Sphinx documentation builder.
#
# This file does only contain a selection of the most common options. For a
# full list see the documentation:
# http://www.sphinx-doc.org/en/stable/config

# -- Path setup --------------------------------------------------------------

# If extensions (or modules to document with autodoc) are in another directory,
# add these directories to sys.path here. If the directory is relative to the
# documentation root, use os.path.abspath to make it absolute, like shown here.
#
import os
import re
from functools import partial
from pathlib import Path
from typing import Callable, Match, Tuple, Union


# -- Version forge -----------------------------------------------------------
def _semver_matcher() -> Callable:
    """Return a func performs regex matching for semantic versions.
       The regex uses word_boundry and is sensitive to the changes
       to the contents of the CMakeLists.txt file. The match should
       have 3 matched groups:
       1. `SET(TI_VERSION_MAJOR `
       2. the corresponding version number
       3. `)`
    """
    return lambda s, w: re.search(rf"(\bSET\(TI_VERSION_{w} )(\d+)(\b\))", s)


def _intify_version(v: Match) -> int:
    """Convert matched group v to integer."""
    return int(v.group(2))


def parse_semver(
    cmakelist_path: str,
    return_match_groups: bool = False
) -> Union[Tuple[int, int, int], Tuple[Match[str], Match[str], Match[str]]]:
    """Parse and return the major, minor and patch version numbers
       (or matched groups) from CMakeLists.txt given CMAKELIST_PATH.
    """
    with open(cmakelist_path, "r") as fp:
        cmakelist = fp.read()
    matcher = partial(_semver_matcher(), cmakelist)
    major, minor, patch = map(matcher, ["MAJOR", "MINOR", "PATCH"])
    if return_match_groups:
        return major, minor, patch
    return tuple(map(_intify_version, (major, minor, patch)))


# CMakeLists.txt is the only source of the truth when forging
# the version, this script always reads from it and parses the version
cmake_file = Path(__file__).resolve().parents[1].joinpath('CMakeLists.txt')
major, minor, patch = parse_semver(cmakelist_path=str(cmake_file))
version_file = Path(__file__).resolve().parent.joinpath("version")
taichi_version = f"{major}.{minor}.{patch}"
print('Building doc version', taichi_version)

# -- Project information -----------------------------------------------------

project = 'taichi'
copyright = '2020, Taichi Developers'
author = 'Taichi Developers'

# The short X.Y version
version = taichi_version
# The full version, including alpha/beta/rc tags
release = taichi_version

# -- General configuration ---------------------------------------------------

# If your documentation needs a minimal Sphinx version, state it here.
#
# needs_sphinx = '1.0'

# Add any Sphinx extension module names here, as strings. They can be
# extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
# ones.
extensions = [
    'sphinx.ext.autodoc',
    'sphinx.ext.doctest',
    'sphinx.ext.intersphinx',
    'sphinx.ext.todo',
    'sphinx.ext.coverage',
    'sphinx.ext.mathjax',
    'sphinx.ext.ifconfig',
    'sphinx.ext.viewcode',
    'sphinx.ext.githubpages',
]

# Add any paths that contain templates here, relative to this directory.
templates_path = ['_templates']

# The suffix(es) of source filenames.
# You can specify multiple suffix as a list of string:
#
# source_suffix = ['.rst', '.md']
source_suffix = '.rst'

# The master toctree document.
master_doc = 'index'

# The language for content autogenerated by Sphinx. Refer to documentation
# for a list of supported languages.
#
# This is also used if you do content translation via gettext catalogs.
# Usually you set "language" from the command line for these cases.
language = None

# List of patterns, relative to source directory, that match files and
# directories to ignore when looking for source files.
# This pattern also affects html_static_path and html_extra_path .
exclude_patterns = []

# The name of the Pygments (syntax highlighting) style to use.
pygments_style = 'sphinx'

# -- Options for HTML output -------------------------------------------------

# The theme to use for HTML and HTML Help pages.  See the documentation for
# a list of builtin themes.
#
html_theme = 'sphinx_rtd_theme'

# Theme options are theme-specific and customize the look and feel of a theme
# further.  For a list of options available for each theme, see the
# documentation.
#
# html_theme_options = {}

# Add any paths that contain custom static files (such as style sheets) here,
# relative to this directory. They are copied after the builtin static files,
# so a file named "default.css" will overwrite the builtin "default.css".
html_static_path = ['_static']

if os.environ.get('READTHEDOCS', '') != '':
    css_files = [
        '//media.readthedocs.org/css/sphinx_rtd_theme.css',
        '//media.readthedocs.org/css/readthedocs-doc-embed.css'
    ]
else:
    css_files = []

html_context = {'css_files': css_files + ['_static/extra.css']}

# Custom sidebar templates, must be a dictionary that maps document names
# to template names.
#
# The default sidebars (for documents that don't match any pattern) are
# defined by theme itself.  Builtin themes are using these templates by
# default: ``['localtoc.html', 'relations.html', 'sourcelink.html',
# 'searchbox.html']``.
#
# html_sidebars = {}

# -- Options for HTMLHelp output ---------------------------------------------

# Output file base name for HTML help builder.
htmlhelp_basename = 'taichidoc'

# -- Options for LaTeX output ------------------------------------------------

latex_elements = {
    # The paper size ('letterpaper' or 'a4paper').
    #
    # 'papersize': 'letterpaper',

    # The font size ('10pt', '11pt' or '12pt').
    #
    # 'pointsize': '10pt',

    # Additional stuff for the LaTeX preamble.
    #
    # 'preamble': '',

    # Latex figure (float) alignment
    #
    # 'figure_align': 'htbp',
}

# Grouping the document tree into LaTeX files. List of tuples
# (source start file, target name, title,
#  author, documentclass [howto, manual, or own class]).
latex_documents = [
    (master_doc, 'taichi.tex', 'taichi Documentation', 'Taichi Developers',
     'manual'),
]

# -- Options for manual page output ------------------------------------------

# One entry per manual page. List of tuples
# (source start file, name, description, authors, manual section).
man_pages = [(master_doc, 'taichi', 'taichi Documentation', [author], 1)]

# -- Options for Texinfo output ----------------------------------------------

# Grouping the document tree into Texinfo files. List of tuples
# (source start file, target name, title, author,
#  dir menu entry, description, category)
texinfo_documents = [
    (master_doc, 'taichi', 'taichi Documentation', author, 'taichi',
     'One line description of project.', 'Miscellaneous'),
]

# -- Extension configuration -------------------------------------------------

# -- Options for intersphinx extension ---------------------------------------

# Example configuration for intersphinx: refer to the Python standard library.
intersphinx_mapping = {'https://docs.python.org/': None}

# -- Options for todo extension ----------------------------------------------

# If true, `todo` and `todoList` produce output, else they produce nothing.
todo_include_todos = True
